Motor pump unit



Fica

FL'OJ.

edezck Doa/d bof'iz' i George -sep/L Y-appl aan? MOTOR PUMP UNIT F.`D. FOQTTIT ETAL.

Filed sept. 9, 1942 /IQO/ April 11', 11944.

Patented Apr. 11, 1944 UNITED y'sm-'rss Moron rumnm'r v i Frederick Donald Foottit and George Joseph Trapp, Leamington Spa, England, assixnors vto Automotive Products Company Limited, LcamingtonSpa, England s Application September 9, 1942, Serial No. 457,754

driving shaft and a multi-cylinder fluid-operated motor having its cylinders arranged around the axis oi' said shaft and extending substantially parallel therewith.

There is further provided for removing liquid from a container a motor pump unit comprising in combination a hollow support having at least three mutually independent passages and an inlet opening adjacent the free end for incoming liquid, a multi-cylinder motor arranged to oe actuated by pressure iiuicl fed through one oi' said passages and to pass the rejected working iiuid through another thereof, and a rotary pump driven by the iiuid pressure motor, said pump being arranged to deliver under pressure through the third passage the liquidwhich enn ters through the inlet opening.

Preferably the duid pressure motor has an obliquely arranged swash-plate with which slids ably engage a series of plunger members extending parallel with the axis of the pump, said plunger members conveniently being slidable within bores formed in a rotatable cylinder blgck, which latter is coupled with the pump by means of a shaft; a packing gland which surrounds this shaft may serve as the sole means for isolating the liquid to be pumped from the working fluid rejected by the motor. If desired the cylinder block may be rotatable upon a spigot and may form a rotary valve controlling the iiow of working fluid into and out of the cylinders of the motor.

The above-mentioned hollow support may comprise an outer tube having a flange or other attachment fitting at one end, and an inlet for the liquid pump at the other, the hydraulic motor conveniently being carried by an inner tube. maintained fconcentrically Within the outer tube, so as to provide, between the inner and outei` tubes, a passage for the liquid delivered by the pump; a pipe may extend longitudinally through thev inner tube to supply pressure fluid to the In Great Britain July 14, 1941 motor, the space between the interior oi the inner tube and the exterior of the pipe conveniently forming a passage through which rejected working fluid leaves the motor. e The invention is illustrated by way of example in the accompanying drawing. in which: Figure 1 is a diagrammatic partly-sectioned elevation of` a petrol tank or like container having the improved pumping unit extending downwards from its top: y

Figure 2 is a similar view withtlhe pump mnt fitted within a sump; l

Figure 3 is a sectional elevation, to an enlarged scale, showing the upper end or the unit as seen .l5 .in Figure l:

Figure e is a sectional elevation, also to an enlarged scale, through the, motor pump portion oi the unit; and Figure 5 is a sectional plan aken on the line 5 5 of Figure e. 1

In the arrangement shown in Figure l a petrol tank or like container it having a. filling cap il is shaped so that its bottom i2 slopes downwards towards a locality indicated at it. The top` it of the tank is bored at `IE5 for the reception of a motor pump unit, which is indicated generally at It and is of elongated cylindrical shape, so thatwhen a. fixing flange il is secured to the top Hi, the bottom or inlet end lt of the a" una le is disposed closely adjacent the locality it. Pressure liquid or other fluid under pressure is fed through an inlet pipe it so as to actuate the motor. which will be hereinafter described,4

the liquid or other fluid repected from said motor being allowed to escape through an outlet pipe 2li. In the meantime the petrol or equivalent -which isdrawn in through the intake i8 passes out under pressure through a delivery Y pipe di.

in In the arrangement shown in Figure 2 the bottom i2 of the tank It is formed with a cylindrlcal sump ita within which the motor pump unit ida is mounted in an inverted position, .the arrangement being such that the intake is is i substantmly on a 1eve1 with the bottom l2 of the tank. The inlet and outlet pipesvfor pressure uid are again indicated at it and 2@ and the petrol or equivalent liquid is arranged-tube forced through a' delivery pipe 2l.

The internal construction of the motor pump unit is shown in Figures 3 to 5. The fixing ange l1 is formed upon a metal block 22, which latter has upon its under surface a pair of concentric (in the embodiment shown in Figure 1) to the motor pump portion of the-device illustrated in and an inner tube 26, which extend downwardly Figure 4. Thus there is screw-threaded intothe lower end of the inner tube 26 an inverted cupshaped member 21 constituting the upper part `of the motor casing, the lower part of said casing being indicated at 28 and being secured to the upper part by studs 29. vTo the upper wall 30 of the motor casing a plate 3| is secured having a spigot 32 which extends through said wall 39 and projects therefrom to form a bearing for a rotatv able cylinder block 33 having a circumferentially arranged series of bores 34 equally spaced around the axis of the'spigot 32 and each being parallel with said waxis. The general arrangement of the bores 34 is shown more clearly in Figure 5. From the upper end of each of the bores 34 a passageway 35 extends obliquely upwards to provide a port for co-operation withone or other of a pair of arcuate-grooves 36 and 31 in that part of ,the spigot 32 disposed within the cylinder block 33. The groove 36 is for lincoming pressure uid, while the groove 31 is for exhaust fluid, the inner end of each passageway 35 communicating alternately with one or the other of the grooves 36 and 31 as the cylinder block 33 rotates, as is common practice in uid pressure motors. The inlet groove 36 is connected by a passage 38 with a bore 39 in the upper part of the spigot 32, which bore is connected with a pipe 46 extending longitudinally through the inner tube 26 and through a packing gland -4i in the block-22, to a connection union said cap being formed with a group of relatively small inlet openings indicated at 59. Thus, owing to the centrifugal action of the blades 56, petrol or like liquid enters through the openings 59 constituting the intake I8 and is delivered in an upward direction through the converging passageway between the cap l and the upturned periphery of the impeller disc 55, said liquid thence flowing through the space 69 between the outer 19a for the inlet pipe i9. In a similar manner 1th'e outlet groove 31 is connected Aby a passage 42 with a'bore 43 in the lower end of the spigot 32 and the exhausted working fluid passes through y this, into a hollow` driving shaft 44 secured coaxially to the cylinder block 33 and then into the interior of the motor casing 21, 28 through one or more radial passages 45 formed inl said shaft -44. 'I'he exhausted liquid can thence now upwards through passages 46 in the circular wall 30 and reach the space 41 between the pipe 40 and the interior of the inner tube 26; the fluid then escapes through a union fitting 20a to the outlet pipe 20.

Each of the bores 34 in the rotatable cylinder block 33 is fitted with a slidable plunger rod 48, the lower end of which is rounded to engage slidably with a swash-plate disc 49 carried by a ball bearing 50, the outer race of which is mounted obliquely inthe lower part 28 of the motor casing. The swash-plate disc 49 is thus able to rotate freely, but it is maintained at all times in its predetermined oblique. plane. In order to reduce friction dueto the upward thrust of the working -liuid upon the cylinder block 33 a thrust ball bearing, indicated at 5I, of the self-aligning type is interposed between the upper surface of the cylinder block 33 and the' circular wall 38.

The driving shaft 44 which is secured to the cylnder block 33 extendsdownwards through the swash-plate disc 49 and the ball bearing 59 and runsin a ball bearing 52 secured in the lower 'part 28 of the motor casing by means of a plate tting 53. The vplate tting 53 also carries a `sealing device or gland 54 of the hat-leather .type designed to prevent the flow of iluid along the shaft 44 in a downward direction. To the lower end' oi the shaft 44 is secured a pump impeller in the form of a domed disc 55 having a series of impeller4 blades 56 formed on its lower surface.

The outer tube 25, which 1s arranged to extend tube 25 and the inner tube 26 and so reaching an outlet connection 2 la to'which the delivery pipe 2| is attached. Thus when the unit has its lower end immersed in liquid, as shown in Figure 1, and pressure liquid vor other uld is fed through tbe inlet pipe I9, said fluid passes through the inlet groove 36, and entering the u xtipi'opriate cylinders 34 causes the cylinder block to rotate owing to the action of the oblique swash-plate disc 49, the rejected fluid being expelled into the motor casing 21, 28 and being returned to the `outlet by way of the space 41. It will therefore be seen that the sealing device or gland 54 can be of an exceptionally light nature, for the pressure of the rejected liquid within the motor casing 21, 28 is only very little greater in normal circumstances than the pressure head of petrol or equivalent acting L' upon the underneath of the seal or v.gland15l.

Indeed, where the unit is used in a petrol tank andy is operated by the liquid normally used by' hydraulic control systems, it has been found that a slight leakage of hydraulic liquid into the petrol is quite harmless. It will-.beseen that as a result of the light nature of the seal or packing gland 54 very little power is wasted and the device is therefore quite efficient.

The lengths of the outer and inner tubes 25 and 26 and of the pipe 48 can be readily arranged to produce units of any desired length, depending upon the depth of the petrol tank or equivalent, or upon the depth at which it is required to position the intake |8. In order to arrange the unit inthe manner shown in Figure 2 the tubes 25v and 26 and the pipe 40 are of such length that the motor casing4 21, 28 is disposed closely adjacent the ange I1, the device in this instance, of course, running in an inverted position with the motor casing 21, 28 disposed below the pump impeller 55, 56. .Whatever the direction of operation it will be seen that'the unit is of relatively small cross-sectional area and thus requires only a hole of corresponding size to be formed in the petrol tank or equivalent for the installation of the unit.

It will of course be understood that the Iconstruction which has .been described is given by way of example and that the invention may be carried into effect in different ways. For instance, other types of pumps, such as the eccentric vane type or the gear wheel type of pump, may be used, and it is conceivable that the device may be employed for pumping gases. Moreover the motor, if desired, may be driven pneumatically. In certain cases va. filter can be incor- :,ssaara nuid fed through one of said passages and l The invention thus provides an exceptionally compact, eidcient and robust form of i'iuid pressure operated pumping unit which is particularly suitable for installation upon air and othei` craft.

What we claim is:

l. For removing liquid from a container, a mo tor pump unit comprising in combination a hollow` support having atleast three mutually inden pendent passages and an inlet opening adjacent the free end for incoming liquid, a multi-cylinder motor arranged to be actuated by pressure iiuid fed through one of said passages and to pass the rejected working fluid through another thereof, and a rotary pump driven by the fluid pressure motor, said pump being arranged to deliver under pressure through the third passage the liquid which enters through the inlet opening.

2,. A motor pump unit of the type which is operable by fluid from a pressure source; compris ing a hollow support having at least three mutually independent passages and. an inlet opening adjacent the free end for incoming liquid, a multi-cylinder motor arranged to be actuated by fluid fed through one of said passages and to pass exhaust iuid through another thereof, said moe tor including a series of plungers mounted for re- I enters the inlet opening.

3. A motor pump unit of the type which is operable by iiuid from a pressure source: compris- ,ing a hollow support having at least three mutually independent passages and an inlet opening exhaust fluid through another thereof, said motor including a rotatable cylinder block having a series of plungers mounted for reciprocation in said cylinders, a swash plate obliquely mounted on the support and adapted to impart rotation to the motor upon reciprocation of said plungers, a rotary pump adapted toy be driven by the pump and connected thereto by a' shaft, and a packing gland surrounding the shaft and held by the support for separating the exhaust fluid from the delivery under pressure through the third passage of liquid which enters the inlet opening.

6. Amotor pump unit of the type which' isoperable by fluid from a pressure source; comprising a hollow support having at least three mutually independent passages and an inlet opening adjacent the free end for incoming liquid, a multicylinder motor arranged to be actuated by nuid fed through one of said passages and in- Y cluding a rotatable cylinder block having a series of plungers mounted for reciprocation in said cylinders. a. spigot connected to the entrance passage and held by the support for forming a journal for the rotatable cylinder block and for forming a valve controlling the flow of actuating iiuid to the cylindersl a swash plate obliquely mounted on the support and adapted to impartrotation to the motor upon reciprocation of said plungers, and a rotary pump adapted to be driven by the motor for delivery under pressure through the third passage the liquid which enters the inlet opening.

prising a hollow support having at least three adjacent the free end for incoming liquid, a mul..l

ti-cylinder motor arranged to be actuated by fiuidfed through one -of said passages and to pass exhaust fluid through another thereof, said motor including a rotatable cylinder block having a series of plungers mounted for reciprocation in said cylinders, a swash plate obliquely mounted on the support and adapted to impart rotation to the motor upon reciprocation oi' said plungers,

and a rotary pump adapted to. be driven by the,

motor for delivering under pressure through` the third passage the liquid which enters the inlet opening. f

fi. A motor pump unit of the type which is op- 'crable by uid fromv a. pressure source; comprising a hollow support having at least three mutually independent passages and an inlet opening adiacentthe free end for incoming liquid, a mul. ti-cylinder motor arranged to be actuated by duid fed through one of said passages and to pass exhaust fluid through another thereof, said motor including a series of plungers mounted for reciprocation in said cylinders, a swash plate obliquely mounted on the support and adapted to impart rotation tothe motor upon reciprocation of said plungers, a rotary pump adapted to be driven by the motor and connected thereto by a shaft, and a packing 'gland surrounding the shaft ,and held by the support for separating the exhaust fluid from'l the .delivery under pressure through the third passage of liquid which enters the inlet opening.

5. A motor pump unit of the type which is operable by fluid from a pressure source; vcomprising a hollow support having at least three mutually independent passages and an inlet opening adjacent the free end for incoming liquid, a multi-cylinder motor arranged to be actuated by mutually independent passages and an inlet opening adjacent the free end for incoming liquid.

a multi-cylinder motor arranged to be actuated by fluid fed through one of said passages and including a rotatable cylinder block.' having a sev ries of plungei's mounted for reciprocation in said cylinders, a. spigot connected to the entrance passage and held by the support for forming a journal for the rotatable cylinder block and for forming a valve controlling the flow ofactuating fluid to the cylinders, a swash plate obliquely mounted on the support and adapted to impart rotation to the motor upon reciprocation of said plungers, and a rotary pump of the centrifugal varied impeller type adapted to be driven by the motor for delivery under pressure through the third passage the liquid which enters the inlet Opening.

8. A motor pump unit of the type which is operable `by fluid from a pressure source; comprising a `hollow support having at least three mutually independent passages and including a pair Voi concentric flanges depending therefrom, a

multi-cylinder motor arranged to be actuated by uid fed through one of said passages and to 'pass exhaust fluid th'rough a second passage and enclosed in a tube s ecured to the inner of said concentric anges, said motor including a series of plungers mounted iorl rcciprocation in said cylinders, a swash plate obliquely mounted in the unsecured end of said tube and adapted to impart rotation to the -motor upon reciprocation oi said plungers,an outer tube concentric with the inner tube for'enclosing a rotary pump driven by said motor and secured to the outer flange and connecting an inlet opening in said outer' tube with the third passage in said support.' said pump being 'adapted to deliver under pressure through prising a hollow support having at least three .mutually independent passages and an inlet opening adjacent the free 'end for incoming liquid, a multi-cylinder motor arranged to be actuated by fluid fed through one of said passages and to pass exhaust fluid through another thereof, said motor including a 'series of plungers mounted for reciprocation in said cylinders, a swash plate obliquely mounted on the support and free to rotate in its oblique plane and adapted to impart rotation tc said motor upon reciprocation of said plungers, a rotary pump adapted to be driven by #the motor for delivering under pressure through the third passage theliquid which enters the inletvopening. 1

1l. A motor pump unit of the type which is tor upon reciprocation of said plungers, a rotary4 on the support-and free td rotate'in its oblique plane and adapted to impart rotation to said mopump, a shaft connecting said pump to said motor and passing through an opening in said swash plate and a. packing gland held in said support intermediate the swash plate and the pump for separang exhaust fluid from the delivery under pressure through the third passage of liquid which enters the inlet opening.

14. A motor pump of the type which is operable by iiuid from a pressure source; comprising a hollow support having at least three mutually independent passages and an inlet opening adjacent the free end for incoming liquid, a multicylinder motor arranged to be actuated by iiuid fed through one of said passages and to passexhaust fluid through another thereof, said motor including a series of plungers mounted for reciprocation in said cylinders, a-swash plate obliquely mounted on the support and free to operable by iiuid from a pressure source;'com

prising a hollow support having at least three mutually independent passages and an inlet opening adjacent th'e free end for incoming liquid, a multi-cylinder motor arranged tol be actuated by fluid fed through one of said passages and to pass exhaust fluid through another thereof, said motor including a. rotatabIe cylinder block having a series of plungers mounted for reciprocation in` said cylinders, a swash plate obliquely mounted on the support and free to rotate'in its oblique plane and adapted to impart rotation to the motor upon reciprocation of said plungers, and

- a rotary pump adapted to be driven :by the motor for delivering underpressure through the third passage the liquid which enters the inlet opening.

j 12. A motor pump unit of the type which is operable by fluid from a pressure source; comprising a hollow support having at least three mutally independent passages land an inlet opening adjacent the free end for incoming liquid, a multi-cylinder motor arranged to be actuated by fluid fed through one of said passages and to pass exhaust uid through another thereof, said motor including a series of plungers mounted for reciprocation in said cylinders, a swash plate obliquely mounted on the support and free to rotate in its oblique plane and adapted to impart rotation to said motor upon reciprocationl of said plungers, al rotarypump, a shaft-connecting said pump to said motor and passing through an opening in said swash plate and a packing gland held in said support intermediate the swash plate and the vpump for separating exhaust fluid from the delivery under pressure through the third passage of liquid which enters the inlet opening.

13 A motor pump unit of the type which is' operable by fluid from a pressure source; comprising a hollow support having at least three l mutually independent passages and an inlet openrotate in its oblique plane and adapted to impart rotation to the motor upon reciprocation of said plungers, a rotary pump adapted to be driven by the motor and connected thereto by a shaft,

.and a packing gland surrounding the shaft and held by the support for separating the exhaust fluid from the `delivery under pressure through the third passage of liquid which enters the inlet opening- 1 15. A motor pump unit of the type which is operable by fluid from a pressure source; comprising a hollow support having at least three mutually independent passages and an inlet opening adjacent the free end for incoming liquid, a multi-cylinder motor arranged to be actuated v byfluid fed through one of'said passages and to passexhaust fluid through another thereof, said motor including a rotatable cylinder block having a series of plungers mounted for reciprocation in said cylinders. a swashplate obliquely mountedon the support and free to rotate in its oblique plane and adapted to impart rotation to the motor uponI reciprocation of said plungers, a rotary pump adapted to be driven by the pump and connected thereto by a shaft, and a pack- .ing glandsurrounding the shaft and heldby the support for separating the exhaust uid from the delivery under pressure through the third passage of liquid which enters the inlet opening.

16. A motor pump unitof the type which isoperable by fluid from a pressure source; com-` prising a` hollow support having at least three mutually independent passages and an inlet opening adjacent the free end for incoming liquid. a multi-cylinder motor arranged to be actuated by fluid vfed through one of said passages and including a rotatable cylinder block having a series of plungers mounted for reciprocation in said cylinders, a spigot connected to the entrance pas- Sarge and held by the support for forming a journal for the rotatable cylinder block and for formingl adjacent the free end for incoming liquid,

a multi-'cylinder motorarranged to be actuated by Yfluid fed through one of said passages and to pass exhaust iiuid through another thereof, said motor includinga rotatable cylinder block having a series of plungers mounted for reciprocation in said cylinders, a swash plate obliquelyv mounted passage the ingfa valve controlling the flow of actuating fluid to the cylinders, a swash plate obliquely mounted on the support. and free to rotate in its oblique plane and adapted to impart rotation-to the -mo tor upon reciprocation of said plungers, and a rotary pump adapted to be driven by. the motor for delivery underpressure throughfthe third liquid which enters the inlet open- 17. A motor pump unitof the type which is operable by uid from apressure source; comprising -a hollow support havingv at least threemutually independent passages and an inlet opening adjacent the free end for incoming liquid, a multi-cylinder motor arranged to be actuated by iluid fed through one of said passages and. including a rotatable cylinder block having a series of plungers mounted for reciprocation in said cylinders, a spigot connected to the entrance passage and held by the support for forming a journal for the rotatable cylinder ,block and for forming a valve controlling the flow of actuating fluid to theA cylinders, a swash plate obliquely l0 mounted on the support and free to rotate in its oblique plane and adapted to Aimpart rotation to the motor upon reciprocation of said plungers, and a rotary pump of the centrifugal vaned impeller type adapted to be driven by the 1'5 motor for delivery under pressure through the thirdpassage the liquid which enters the inlet opening. 18. A motor pump unit of the type which is `operable by iiuid from av pressure source; comprising a hollow support having at least three mutually independent passages and including a pair of concentric flanges depending therefrom, a multi-cylinder motor arranged to be actuated -by fluidy fed through one of said passages and to pass exhaust fluid through a second passage and enclosed in a tube secured to theinner of said concentric flanges, said motor including a series o1' plungers mounted for reciprocation in said cylinders, a swash plate obliquely mounted in the unsecured end of said tube and free to rotate in its oblique plane and adapted to impart rotation to the motor upon reciprocation of said plungers, an outer tube concentric with the inner tube for enclosing a rotary pump4 driven by 35 said motor and secured to the outer iiangeand connecting an inlet opening in said outer tube with the third passage in said support, said pump being adapted to deliver under pressure through.

the third passage the liquid which enters the inlet opening.

19. The invention as dened in claim 18, wheref in a pipe extends longitudinally through the inner tube to supply actuating fluid Yto the motor and the inner tube is connected to the second Journal for the rotatable cylinder block and for' forming a valve controlling the flow of actuating fluid to the cylinders, a swash plate obliquely mounted on the support and adapted to impart rotation to the motor upon reciprocation of said plungers, a rotary pump adapted to be driven by the motor for delivery under pressure through the third passage the liquid which enters the inlet opening, and a packing gland held by said support for separating the exhaust fluid from the delivery under pressure through the third passage of liquid which enters the inlet opening.

21. A motor pump unit of the type which is operable by fluid from a pressure source; comprising a hollow support having at least three mutually independent passages and an'inlet opening adjacent the free end for incoming liquid, a multi-cylinder motor arranged to be actuated by fluid fed through one of said passages and including a rotatable cylinder block having a series of plungers mounted for reciprocation in said cylinders, a spigot connected to the entrance passage and held by the support for forming a journal for the rotatable cylinder block and for forming a valve controlling the iiow of actuating uid to the cylinders, a swash plate obliquely mounted on the support and adapted to'impart rotation to the motor upon reciprocation of said plungers, aI rotary pump of the centrifugal varied impeller type adapted to be driven by the motor for delivery under pressure through the third passage the liquid which enters the inlet open,- ing, and a packing 'gland held in said support for separating the exhaust uid from the delivery under pressure through vthe third passage of liquid which enters the inlet opening.

.FREDERICK DONALD FOO'I'I'IT. GEORGE JOSEPH TRAPP. 

